The ability to safely and efficiently climb or scale trees, wooden poles such as telephone or powerline poles, and similar structures or surfaces is useful for reaching elevated hunting blinds, servicing utility wires, and the like. Although ropes and ladders are sometimes used for climbing, it is also known to install transportable steps that can be driven into a tree or pole to provide hand holds or foot supports to aid in climbing. Typical screw-in steps, for example, are forced against a tree or pole while turning the entire step, which can be particularly difficult or dangerous to accomplish because it typically requires the use of two hands. This may be especially difficult or dangerous when the user has already climbed part way up the tree or pole. Other known devices include tree-climbing “sticks” that are typically strapped to a tree, and that include a plurality of steps for use in scaling the tree.